Sheet feed press for printing small size sheets on both sides simultaneously

ABSTRACT

This press has three rubber rollers. Two contacting rubber rollers of same diameter have 180* cut-outs receiving printing plates of any angular extent up to 180* with the rubber of each one contacting the plate of the other as these two rollers roll in opposite directions by means of gearing. When the printing plate is a full 180*, the rubber layer on one roller always contacts the printing plate of the other. The third roller is rubber all around and has a circumference equal to half of the circumference of each of the first two rollers. A single inking system applies ink to the first of the two rollers. Thus, the first of the two rollers accomplishes a double function as plate and inkroller, the second of the first two rollers has the function of a plate and blanket roller and the third smaller roller acts as a blanket and impression roller, so that a sheet fed between the second of the two rollers and the smaller roller, is printed on both sides simultaneously.

United States Patent Dreyer [4 1 Sept. 12, 1972 [54] SHEET FEED PRESS FOR PRINTING SMALL SIZE SHEETS ON BOTH SIDES SIMULTANEOUSLY [21] Appl.N0.: 151,747

' [56] References Cited UNITED STATES PATENTS 2,539,383 l/l95l Davidson ..10l/217 UX 2,911,907 11/1959 Davidson ..101/137 Primary Examiner-J. Reed Fisher Attorney-J. B. Felshin [57] ABSTRACT This press has three rubber rollers.- Two contacting rubber rollers of same diameter have 180 cut-outs receiving printing plates of any angular extent up to 180 with the rubber of each one contacting the plate 'of the other as these two rollers roll in opposite directions by means of gearing. When the printing plate is a full 180, the rubber layer on one roller always contacts the printing plate of the other. The third roller is rubber all around and has a circumference equal to half of the circumference of each of the first two rollers. A single inking system applies ink to the first of the two rollers. Thus, the first of the two rollers accomplishes a double function as plate and inkroller, the second of the first two rollers has the function of a plate and blanket roller and the third smaller roller acts as a blanket and impression roller, so that a sheet fed between the second of the two rollers and the smaller roller, is printed on both sides simultaneously.

12 Claims, 6 Drawing Figures PAIENIEnsmzmz 3.690.253

sum 2 or 2 INVENT 5/01 E. Veil wsgojl-w -1 SHEET FEED PRESS FOR PRINTING SMALL SIZE SHEETS ON BOTH SIDES SIMULTANEOUSLY This invention relates to a sheet feed press for printing sheets simultaneously on both sides.

An object of this invention is to provide a printing press of the character described using only one inking system to'ink both a front printing plate and a back printing plate and print both images on rubber rollers and finally print both sides of sheets simultaneously, pressed rubber to rubber, thereby necessitating only one ink fountain and one set of inkrollers for both sides of the sheet. With the present press, washing of the rollers, blankets and plates at the same time is facilitated.

. Another object of this invention is to provide a highly simplified printing press construction of the character described-which will ease the operation for the pressman to such extent that he will have no more difficulty printing both sides of the paper sheet than he would have printing one side only on a usual offset press.

With this new press the operator seeing the print on one side of the paper, will know that the other side is being printed with the sameinkflow that supplies ink for printing the first side.

Because of the relatively small size and the texture of cards, envelopes or other sheets to be printed, in addition to the rubber torubber impression whereby the she'etlis under full control during the entire printing cycle, there is no need for grippers to pull thesheet to be printed, through the press as on other sheet fed printing presses, and they are therefore eliminated. For that reason this press is capable of printing sheets with little or no flexibility, such. as stiff cardboardor plastic sheets. All modern printing presses have cylinder steel bearers to stabilize and control the impression between the cylinders. These bearers are part of the cylinders and situated on each end of said cylinder around the circumference. y

. While the press is printing, the bearers of one cylinder are in contact under pressure with the bearers of the opposing cylinder, as plate cylinder is against blanket cylinder or blanket cylinder is against impression cylinder.

Because of this (steelbearers against steelbearers) the cylinders cannot be moved closer, or away from each other for more or less impression on .prior presses.

Because this invention consists of rubber rollers instead of steel cylinders it is possible to increase or lessen the pressure against the bearers on all three cylinders and thereby saving costly time adjusting the pressure by adding or subtracting sheets of paper under the blanket or printing plate.

This adjustment is done by moving the middle rubber roller closer or further away from the two other rollers both of which rotate on fixed axes.

This middle roller is attached to an adjustable lever on each side which is attached to the bearing which holds the top roller.

This lever is split between the top and middle roller by two threaded rods of different pitch and held together by a nut with the two matching different threads, and a lock nut for holding the pressure once it is set. This arrangement permits the adjustment of pressure between the two rollers.

This adjustment will remain unaffected when the pressure adjustment between the middle roller and the lower roller is changed because the lever swings on the axis of the top roller.

This adjustment (center roller against the lower roller) is set by a screw behind a large electro-magnet which is activated whenever a sheet is fed from the feeder to the printing unit, thereby pulling the lever toward it and making contact between the center roller and the lower roller.

Unless a sheet is fed into the printing unit the electromagnet is deactivated and a spring will pull the lever away and thereby move the center roller off impression.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements, and arrangement of parts, which will be exemplified in the construction hereinafter described, and of which the scope of invention will be indicated in the following claims.

In the accompanying drawings in which is shown various illustrative embodiments of this invention,

FIG. 1 is a perspective view of the press embodying the invention;

FIG. 2 is an end view of the press with the inking rollers omitted;

FIG. 3 is an enlarged cross-sectional view taken on line 33 of FIG. 2;

FIG. 4 is a transverse, vertical cross-sectional view of the structure shown in FIG. 1;

FIG. 5 is a view similar to FIG. 4, but showing the first two rollers moved from the position of FIG. 4.

FIG. 6 is a diagramatic view illustrating control of the electro-magnet by movement of the sheet to be printed.

Referring now in detail to the drawing, 10. designates a printing press embodying the invention. Said press comprises inking rollers 11 receiving ink in a usual manner. The press has side frames 12 and 13 on which the inking rollers 11 are rotatably mounted- Supported by said frames 12, 13 for rotation is a shaft 14 carrying a coaxial steel roller 15 having a rubber outer layer 16. The shafts 14 rotate in fixed bearings on the frame. The rubber layer 16 has a cutout l7'which extends 180 circumferentially but terminates short of the ends of the rubber layer. The cutout exposes the steel cylindrical roller. Attached to the exposed semi-cylindrical surface of the steel roller is a printing plate 18 having a circumferential extent of any size up to 180.

Rotatably mounted on axle 14 at one side of the press (the near side looking at FIG. 1) is an impression lever or arm 20.-The arm 20 is shown on one side only of the press. Ann 20 comprises a ring portion 21 journalling the shaft 14. Extending from ring 21 is a radial stem 22 having a threaded end 23. 0n threaded portion 23 is a lock nut 24 (FIG. 3). Also on threaded portion 23 is screwed a turnbuckle nut 25. Said nut 25 has an upper inner thread 26 having a pitch similar to the pitch of screw portion 23 and similar to the pitch of lock nut 24. Said turnbuckle nut 25 has a lower inner threaded portion 27. Screwed into thread 27 is a threaded end 28 of a rod 29. The threads of portions 27, 28 is of a lesser pitch than the pitch of threaded portions 23, 26 and of the internal threads of lock nut 24. Rod 29 is aligned with stem 22. Extending from rod 29 is a ring 30 from which extends a rod 31 coaxial with rod 29. Thus, members 20 can rotate about the fixed common axis of shafts l4 and roller 15.

Rotatably mounted on and in ring 30 of member 20 is an axle 34. There are two coaxial axles 34, carrying a coaxial steel cylindrical roller 35 therebetween on which is fixed a rubber layer 36. At the far side of the press is an arm (not shown) similar to arm 20 except that arm portion 31 may be eliminated. The opposite axle 14 is journalled in ring 21 of the other arm 20, and the other axle 34 is journalled in the ring 30 of said other arm. Rollers 15, 35 have interengaging or meshing gears a, 35a respectively. The gears 15a, 35a are similar. The outer diameter of rubber layers 16, 36 are similar.

The layer 36 has a cut out 37 of any angular extent up to 180 circumferential extent and terminating short of the ends of said rubber layer. Fixed to the steel roller and disposed within cut-out 37 is a printing plate 38 of any size up to 180 circumferential extent. The cut-out 37 is so located that the plate 18 will contact only the rubber 36 of roller 35, and the plate 38 will only contact the rubber 16 of roller. 15. Swinging of the arms will not move the roller 35 out of contact with respect to roller 15.

Shafts 34 may move about the axis of shafts 14 and rotate about their own axes.

Rotatably mounted on frames 12, 13 in suitable bearings is a roller 40, comprising a steel inner cylinder or drum 41 covered by a rubber layer 42. Layer 42 has annular grooves 43 located at the end of plate 38. The smaller roller 40 has a diameter, and hence a circumference, half the size of rollers 15, 35. Roller 40 has a gear 45 which meshes with gear 35a. One revolution of gear 35a causes two revolutions of gear 45. Hence roller 40 turns twice for one revolution of each of rollers 15, 35.

A coil tension spring 50 is interposed between the lower end of arm 20, at the rear side of the press, and an abutment 52 on the press frame. Screwed to the frame is a screw 53 which adjustably engages the lower end of an electro-magnet 54 having an upper end adjacent the outer end of arm portion 31.

The sheets '55 to be printed are fed between rollers 35, 40 in the direction shown by the arrow in FIG. 5. Any suitable switch may be provided, adapted to close when the paper is fed between the rollers, to energize a circuit for the electro-magnet 54, to swing the arm 20 downwardly and press the rollers 15, 35 together.

After the sheet passes through and beyond the rollers, the switch opens and the electro-magnet is deenergized and spring 50 raises the roller 35 from the roller 40, slightly.

It will now be understood that the one inking system 11 supplies ink for printing on both sides of the sheets 55. The inking rollers ink the plate 18 and the rubber layer 16.

The rubber layer 16 is inked during l/2 revolution of roller 15. During the second one-half revolution of roller 15, plate 18 is inked by the inking system 11. During this time, the plate 38 is inked by rubber layer 16. During the following one-half revolution, the plate 18 prints on the rubber layer 36 and the plate 38 prints on layer 42 of roller 40. On the final one-half revolution the actual printing occurs, as the sheet of paper 55 passes between rollers 35 and 40 and receives the images from rubber layer 36 and rubber layer 42. Roller 40 makes twice as many revolutions as rollers 15 and 35, which permits it to receive the impression from plate 38 every other revolution and print that image on the underside of the paper on the next revolutions of roller 40.

Unlike other sheet fed printing presses, there are no grippers necessary because the sheet is under constant pressure between the rollers 35, 40.

The plate 18 prints on rubber 36 which prints on the upper side of the sheet while the roller 40 prints on the underside of the sheet.

The rollers 15 and 35 may be 3 inches in diameter, 12 inches long with 4 inch long and 1 inch diameter shanks or shafts. The gears 15a, 35a may be detachable.

The rubber layers or coatings 16, 36 may be A inch in thickness. The cut-out may be 10% inches long and 5% inches in curvature. The printing plates may be glued on the steel cores of the rollers. The printing plates used for this press are relief plates with the printing area higher than the non-printing area. The printing plates may be made of Dycril, rubber, zinc or other suitable material.

The maximum printing area may be 10 inches by 5 inches.

Roller40 may have a stainless steel core 41 of same length as rollers 15, 35, and only be 1 inches in diameter. The shanks or shafts on roller 41 may be the same as rollers 15, 35 in length and diameter with a detachable gear one-half the circumference of the gears on rollers 15, 35. The rubber layer 42 may also be A inch in thickness with the grooves 43 of A inch width, located about 1 inch from each end. These 1 inch wide rubber ends correspond with the ends of the rubber layers 16, 36 on rollers 15, 35, beyond the cutouts, and act as bearers during the printing cycles. The 41inch wide grooves keep the ink from roller 35 from entering the printing surfaces of layer 42, of roller 40.

The on, off impression lever or arm 20 and the opposite arm (not shown) carry the roller 35.

By loosening the lock nuts 24, and manipulating the turnbuckle nuts 25 of both impression levers, the degree of contact between rollers 15, 35 may be ad justed. This is so because the pitch of screw threads 26 is greater than the pitch of screw threads 27. However arm portions 31 and 22 remain in alignment. The degree of contact between rollers 35 and 40 is controlled by the screw 53.

Referring now to FIG. 6, it will be seen that when the sheet 55 is about to enter between the rollers, 35, 40, switch will close to energize electro-magnet 54 through any suitable circuit 71. When the paper passes through the rollers, switch 70 opens to deenergize the electro-magnet.

It will thus be seen that there is provided a device in which the several objects of this invention are achieved and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative.

With the present press a metal surface plate cannot be used as there is no provision to print wet" offset on this press. Also this press cannot print different colors on the two sides.

Due to elimination of the grippers, the sheet can be printed on its entire surface on both sides. This cannot be done on a press with grippers because of the gripper bite on the front end of the sheet.

I claim:

1. A printing press comprising inking means, a first roller positioned to receive ink from said inking means, said roller having a part cylindrical printing plate portion and a part cylindrical coextensive ink roller portion, a second roller having a part cylindrical printing plate portion and a part cylindrical blanket portion coextensive therewith, means to maintain said first and second rollers, in rolling contact, coextensively, said rollers being of the same diameter, means to connect said rollers for rotation abouttheir axes in opposite directions at the same rate of rotation, with the printing plate portion of the first roller contacting the blanket portion of the second roller and the ink roller-portion second and third rollers during a following half revolution of said first roller, during which time the third roller makes another complete revolution.

2. The combination of claim 1, and means to rotate the second roller about the axis of the first roller.

3 The combination of claim 1, and means to adjust the distance between the axes of said first and second of the first roller contacting the printing plate portion of t he'secondroller, and a third roller comprising an outer blanket all around and being coextensive with said second roller and of a diameter half the diameter of the first or second rollers, means to connect said third roller .for rotation about its axis, two revolutions for each revolution of the first or second rollers, in contact with said second roller, whereby ink from the inking means will ink the ink roller portion of the first roller during the first half revolution of said first roller, and will ink the printing plate portion of the first roller during the second half revolution of the first roller, and

the inked ink roller portion of the 1st second roller during the will ink the printing plate portion of the second roller during the second half revolution of the'first roller, and the printing plate portion of the first roller will impress the blanket portion of said the next half revolution of the first roller, and the printing plate portion of the second roller will impress the blanket of the third roller during said next half revolution of said first roller, during which time said third roller makes a full revolution, and whereby said blanket portion of said second roller and said blanket of said third roller may print opposite sides of a sheet passing between said rollers.

4. The combination of claim 1, means to move the second roller in one direction, about the axis of the first roller and means to move the second roller in an opposite direction about the axis of the first roller.

- 5. The combination of claim 4, and means to limit movement of the second roller in one of said directions.

6. The combination of claim 1, means to rotate the second roller about the axis of the first roller, and means to vary the distance between the axes of said f t and s r llers.

7. The i binaiion of claim 1, said ink roller portion of the first roller comprising an outer layer of rubber,-

said outer layer having a cut-out terminating short of the ends of said layer, and said printing plate portion of the first roller being recessed into said cut-out and fixed to the first roller, said cut-out and printing plate terminating short of the ends of the roller.

8. The combination of claim 7, the blanket portion of said second roller comprising an' outer rubber layer terminating short of the ends of said layer and having a cut-out, and said printing plate being recessed into said cut-out in the-blanket portion of said second roller and fixed to said second roller.

' 9. The combination of claim 8, said blanket of said third roller comprising an outer layer of rubber.

10. The combination of claim '9, said outer layer of said third roller having annular grooves spaced from the ends of said outer layer and located at the ends of I the printing plate portion of said second roller.

1 l. The combination of claim 1, each of said printing plate portions of said first and second rollers being in circumferential extent.

12. The combination of claim 1, electro-magnetic means to move said second roller toward said third roller, and means controlled by a sheet passing between said second and third rollers, to control said electromagnetic means. 

1. A printing press comprising inking means, a first roller positioned to receive ink from said inking means, said roller having a part cylindrical printing plate portion and a part cylindrical coextensive ink roller portion, a second roller having a part cylindrical printing plate portion and a part cylindrical blanket portion coextensive therewith, means to maintain said first and second rollers, in rolling contact, coextensively, said rollers being of the same diameter, means to connect said rollers for rotation about their axes in opposite directions at the same rate of rotation, with the printing plate portion of the first roller contacting the blanket portion of the second roller and the ink roller portion of the first roller contacting the printing plate portion of the second roller, and a third roller comprising an outer blanket all around and being coextEnsive with said second roller and of a diameter half the diameter of the first or second rollers, means to connect said third roller for rotation about its axis, two revolutions for each revolution of the first or second rollers, in contact with said second roller, whereby ink from the inking means will ink the ink roller portion of the first roller during the first half revolution of said first roller, and will ink the printing plate portion of the first roller during the second half revolution of the first roller, and the inked ink roller portion of the 1st second roller during the will ink the printing plate portion of the second roller during the second half revolution of the first roller, and the printing plate portion of the first roller will impress the blanket portion of said the next half revolution of the first roller, and the printing plate portion of the second roller will impress the blanket of the third roller during said next half revolution of said first roller, during which time said third roller makes a full revolution, and whereby said blanket portion of said second roller and said blanket of said third roller may print opposite sides of a sheet passing between said second and third rollers during a following half revolution of said first roller, during which time the third roller makes another complete revolution.
 2. The combination of claim 1, and means to rotate the second roller about the axis of the first roller.
 3. The combination of claim 1, and means to adjust the distance between the axes of said first and second rollers.
 4. The combination of claim 1, means to move the second roller in one direction, about the axis of the first roller and means to move the second roller in an opposite direction about the axis of the first roller.
 5. The combination of claim 4, and means to limit movement of the second roller in one of said directions.
 6. The combination of claim 1, means to rotate the second roller about the axis of the first roller, and means to vary the distance between the axes of said first and second rollers.
 7. The combination of claim 1, said ink roller portion of the first roller comprising an outer layer of rubber, said outer layer having a cut-out terminating short of the ends of said layer, and said printing plate portion of the first roller being recessed into said cut-out and fixed to the first roller, said cut-out and printing plate terminating short of the ends of the roller.
 8. The combination of claim 7, the blanket portion of said second roller comprising an outer rubber layer terminating short of the ends of said layer and having a cut-out, and said printing plate being recessed into said cut-out in the blanket portion of said second roller and fixed to said second roller.
 9. The combination of claim 8, said blanket of said third roller comprising an outer layer of rubber.
 10. The combination of claim 9, said outer layer of said third roller having annular grooves spaced from the ends of said outer layer and located at the ends of the printing plate portion of said second roller.
 11. The combination of claim 1, each of said printing plate portions of said first and second rollers being 180* in circumferential extent.
 12. The combination of claim 1, electro-magnetic means to move said second roller toward said third roller, and means controlled by a sheet passing between said second and third rollers, to control said electro-magnetic means. 